AA 337 then DL 5706 at Philadelphia
Salt Lake City → Philadelphia → Boston
Timetable, Philadelphia time
13:13AA 337 from Salt Lake City at the gate
16:29DL 5706 to Boston leaves the gate
3 h 16 apart on the timetable
The last days
AA 337 and DL 5706 weren’t both flown 15 min to 12 h apart in the last 21 days.
Statistics from past flights, not live flight information. Always check times and your connection with your airline, and don’t base travel or booking decisions on these numbers.